1. Field of the Invention
The present invention is directed to expansion joint assemblies and methods of making these and is more particularly directed to such expansion joint assemblies as are improved to substantially reduce erosion and other detrimental effects of rain water and other fluid roadway runoff. The invention is directed to the protection of concrete, metal and other materials of a joint in a roadway, bridgeway, parking garage or the like and to the orderly removal of rain, acid rain and other fluid materials.
2. Prior Art Statement
Numerous patents have issued over the years to various types of expansion joints for roadway sections, deck structures for highway bridges, parking lots or the like. The basic prior art arrangement involves spanning an expansion gap with some form of elastomeric material or combination of such material with metal pieces to allow for thermal expansion and contraction of the adjoining sections of roadway or the like. Some prior art arrangements involve elastomeric units of oval or heart shaped or ringlet type designs so as to create increased strength but to still permit reasonable expansion and contraction. However, over the years, many efforts have been made to prevent water, acid rain and other fluids which run off roadway surfaces and bridgeways down through the expansion joints and frequently create corrosion problems or other types of deterioration problems for the underlying concrete.
A number of patents, including U.S. Pat. Nos. 4,271,650; 4,295,315; 3,750,359 and 3,677,145 are directed to various types of expansion joints and specifically disclose the use of a V-shaped or U-shaped channel which is formed in the base and is connected to both sides of the roadway or bridgeway joint. This channel is typically made of flexible or semi-flexible material and is designed to widen or close depending upon the expansion or contraction of the joint. However, all of these channel type run off arrangements involve the use of specifically designed and custom arranged armor or metal plate sections for the roadway which are adapted to receive these channels and, for that reason, these channels are not retrofitable to existing expansion joints. Further, due to the fact that they are connected to both sides of an expansion joint, while they may work well for perfect expansion and contraction, they may undergo serious stresses and fracture or rip when the roadway sections shift asymmetrically, or move out of perfect parallelism, or hinge either in the vertical central axis or move to create a hinge effect in the horizontal plane. In other words, real world expansion joints may frequently be exposed to complex angle expansions and this may create permanent damage to drainage channels which are taught in the prior art. Additionally, the U-shaped and V-shaped channels will collect a buildup of debris and ice which cannot be exposed to upwardly moving hot air which would aid in thawing any built up icing.
The present invention is directed to an expansion joint assembly which allows for rain, water and other fluid runoff and thereby protects expansion joint materials while also overcoming the problems inherent in the U-shape and V-shape channel type systems of the prior art. Thus, the present invention is directed to an expansion joint assembly and method which may be applied to structures already in place as well as to newly created structures and the retrofitting features make the present invention assembly much more universal than those taught in the prior art. Additionally, the present invention assembly allows for movement of warm air upwardly to reduce freezing and ice damage as well as clogging and may be custom arranged to suit the particular geometry of a given expansion joint.